A Novel Approach and Design of Embedded Controlled Prosthetic Upper Limb to Assist the Above Elbow Amputees

摘要

The existing prosthetic upper limb design and control is divided into two broad categories. One is the myoelectric prosthesis where electromechanical active joints actuate the arm segments and is directly activated by acquiring Electromyogram (EMG) signals from the amputee which is sensed by myoelectric electrodes. Acquiring of the EMG signals is a tedious process as it involves adequate amplification and proper filtering. Also isolation of noise from EMG signals poses difficulty. The other category falls under intelligent prosthetic hand where neural networks (NN) are involved. It requires adequate training for NN operation that leads to the complexity in implementing electronic circuits. The major disadvantage of the above mentioned technologies is lack of proprioceptive feedback from the amputee. The drawbacks of the existing technologies motivates us to design a prototype with proprioceptive feedback to control the Above Elbow (AE) prosthesis with a permanent magnet implanted at the distal end of the residual humerus of the amputee. The proprioception remains intact to the residual limb skeletal structure. In this work, the proposed approach involves in processing the magnetic field variation due to residual arm bone movement which is sensed by magnetic field sensors. The embedded controller controls the movements of the prosthetic hand by processing the signals received from the sensors to assist the AE amputee.